Pulmonary Alveolar Microlithiasis: Radiographic and Scintigraphic Correlation

Abstract

Pulmonary alveolar microlithiasis (PAM) is one of many causes of calcium deposition within the lungs. A rare condition, PAM describes an acquired process in which calcific bodies are deposited into the pulmonary alveolar space. The authors present the imaging findings of a patient with PAM. This case demonstrates how Tc-99m methylene diphosphonate (MDP) bone scintigraphy, in conjunction with chest radiography and computerized tomography, contributed to the diagnosis of PAM in a middle-aged woman who was initially misdiagnosed. Bone scintigraphy may add helpful information in the case of nonspecific CT findings. The usual picture is that of intense bilateral uptake of the radiopharmaceutical in the lungs.

Pulmonary Alveolar Microlithiasis:AIRP Best Cases in Radiologic-Pathologic Correlation

“…Bronchiectasis may result from fibrosis, but it is often peripheral and mild (9). Although not routinely performed, technetium Tc 99m medronate bone scanning can reveal diffuse bilateral radionuclide uptake concentrated at the lung bases (15).…”

Diffuse Pulmonary Uptake of Tc-99m Methylene Diphosphonate in a Patient with Non-tuberculosis Mycobacterial Infection

“…And bone scintigraphy may be useful for differential diagnosis through providing information about disease activity [17][18][19][20]. The extent of the miliary infiltration improved in the subsequent chest CT in our patient.…”

Metastatic pulmonary calcification on bone scintigraphy of a patient with lupus nephritis and end-stage renal disease

“…Diffuse lung calcification may rarely occur secondary to pulmonary alveolar microlithiasis (PAM) and may present with elevated pulmonary Tc99m-MDP uptake on bone scan similar to MPC [ 13 , 14 ]. A rare, autosomal recessive disorder, PAM causes widespread deposition of calcium phosphate microliths throughout the lungs without disruption of calcium metabolism.…”